www.getfirefox.com - I've been using it for a year and a half exclusively. You'll notice that a lot of things in IE7 were copied from Firefox, but they just work better in Firefox.
Plus, when you install Ad-Block Plus, you don't see ANY ads on ANY website, ever - https://addons.mozilla.org/en-US/firefox/addon/1865
But really, those problems you describe don't seem to be strictly IE7 related.. there could be something else going on, such as spyware or a virus. I have IE as do all Windows computers, and when I use it, it works fine. I just don't like it. Try a couple free security scans, too: http://security.symantec.com
Download Windows Defender from Microsoft: http://www.microsoft.com/athome/security/spyware/software/default.mspx
Do you have anti-virus software?
Then again you may just have too many programs running at startup.